Line Plots

plot(x, y, options);

where x and y are vectors of data and options represents many of the possible options for the plot command. If only one vector of data is passed, then the vector values will be plotted against their index. Options may be globally set using the par(...) command. The plot and par documentation lists the options that may be specified.

Use the lines(...) to plot additional data on an existing plot.

One can include parameters listed under the par command explicitly in a plot(..) call. (These parameters will only apply to current plot call).

One can create mathematics in plot labels and titles using plotmath.

Useful commands related to creating plots :

lines(...)	Plots additional lines on a given plot. See lines for details
par(...)	Sets the default parameters for plotting. See par for details.
windows(...)	Opens up a new graphics window for plotting. See windows for details. Use the GUI windows selection to manage multiple plot windows.
grid(...)	Adds a grid lines to the plot. See grid for details.
screen(...) split.screen(...) erase.screen(...) close.screen(...)	Commands for creating multiple plots on a single page. See screen for details (and samples below).

See Also : Printing/Saving plots

Original Documentation : plot, lines, par, windows, grid, screen, plotMath

Samples

# Generating x,y data for a sin function, then plot with a solid line

  x <- seq(0.0,2.0*pi,.1);
  y <- sin(x);
  plot(x,y,type='l');

# Generating x,y data for sin and cos functions, then plotting in the same plot

  x <- seq(0.0,2.0*pi,.1);
  y <- sin(x);
  z <- cos(x);
  plot(x,y,type='l');              # plot sin
  lines(x,z,type='l',col="blue");  # plot cos as blue line

# Generating x,y data for a sin function and then plotting in a window
# with x and y ranges [0.0,2.0*pi] x [-1.5,1.5].

  x <- seq(0.0,2.0*pi,.1);
  y <- sin(x);
  plot(x,y,type='l',xaxs='i',yaxs='i',xlim=range(0,2*pi),ylim=range(-1.5,1.5));

# Creating a two plots on a single page.

  x <- seq(0.0,2.0*pi,.1);
  y <- sin(x);
  z <- cos(x);
  split.screen(c(2,1));
  screen(1);              # select screen 1 to plot on
  plot(x,y,type='l');     # plot sin 
  screen(2);              # select screen 2
  plot(x,z,type='l');     # plot cos
  close.screen();         # close split screen mode

# Creating plots on two separate pages

  x <- seq(0.0,2.0*pi,.1);
  y <- sin(x);
  z <- cos(x);
  plot(x,y,type='l');     # plot sin 
  windows();              # create a new graphics window
  plot(x,z,type='l');     # plot cos in new window 

#
# A plot with a title that contains mathematics (the paste command concatenates strings)
#

  aTitle <- expression(paste("f(x) = ", over(1,1 + x^2)));
  x <- seq(-5.0,5.0,.1);
  y <- 1.0/(1.0 + x^2);
  plot(x,y,type='l',col='blue',main=aTitle); 

#
# Using the par command to set plot options, and then restore them
#

  oldPar <- par(xaxs='i',yaxs='i',lwd=2,font.lab=2); # set new options
  x <- seq(-5.0,5.0,.1);
  y <- 1.0/(1.0 + x^2);
  plot(x,y,type='l',col='blue'); 
  par(oldPar);                                       # restore original

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